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Bensebaa F.,NRC Institute for Chemical Process and Environmental Technology
Progress in Photovoltaics: Research and Applications | Year: 2011

There are very few published data comparing performance and cost of thermal and photovoltaic (PV) based solar power generations. With recent intense technology and business developments there is a need to establish a comparison between these two solar energy options. We have developed a simple model to compare electricity cost using these two options without any additional fuel source of hybridization. Capital along with operation and maintenance (O&M) costs and other parameters from existing large scale solar farms are used to reflect actual project costs. To compete with traditional sources of power generation, solar technologies need to provide dispatchable electric power to respond to demand during peak hours. Different solutions for energy storage are available. In spite of their high capital cost, adding energy storage is considered a better long term solution than hybrid solar systems for large scale power plants. For this reason, a comparison between the two solar options is also provided that include energy storage. Although electricity storage is more expensive than thermal storage, PV power remains a competitive option. Expenses related to O&M in solar thermal plant are about ten times higher than PV, an important factor resulting in higher energy cost. Based on data from proven commercial technologies, this study showed that PV holds a slight advantage even when energy storage is included. © 2010 Crown in the right of Canada.

Farhad S.,Carleton University | Yoo Y.,NRC Institute for Chemical Process and Environmental Technology | Hamdullahpur F.,University of Waterloo
Journal of Power Sources | Year: 2010

The performance of three solid oxide fuel cell (SOFC) systems, fuelled by biogas produced through anaerobic digestion (AD) process, for heat and electricity generation in wastewater treatment plants (WWTPs) is studied. Each system has a different fuel processing method to prevent carbon deposition over the anode catalyst under biogas fuelling. Anode gas recirculation (AGR), steam reforming (SR), and partial oxidation (POX) are the methods employed in systems I-III, respectively. A planar SOFC stack used in these systems is based on the anode-supported cells with Ni-YSZ anode, YSZ electrolyte and YSZ-LSM cathode, operated at 800 °C. A computer code has been developed for the simulation of the planar SOFC in cell, stack and system levels and applied for the performance prediction of the SOFC systems. The key operational parameters affecting the performance of the SOFC systems are identified. The effect of these parameters on the electrical and CHP efficiencies, the generated electricity and heat, the total exergy destruction, and the number of cells in SOFC stack of the systems are studied. The results show that among the SOFC systems investigated in this study, the AGR and SR fuel processor-based systems with electrical efficiency of 45.1% and 43%, respectively, are suitable to be applied in WWTPs. If the entire biogas produced in a WWTP is used in the AGR or SR fuel processor-based SOFC system, the electricity and heat required to operate the WWTP can be completely self-supplied and the extra electricity generated can be sold to the electrical grid. Crown Copyright © 2009.

Kim D.S.,Sensors and Electrochemical Devices Group | Labouriau A.,Los Alamos National Laboratory | Guiver M.D.,NRC Institute for Chemical Process and Environmental Technology | Kim Y.S.,Sensors and Electrochemical Devices Group
Chemistry of Materials | Year: 2011

Guanidinium-functionalized poly(arylene ether sulfone) anion exchange polymer electrolytes were synthesized via activated fluorophnyl-amine reaction, followed by the methylation with dimethyl sulfate. The activated fluorine-amine reaction gives precise control of cation functionality without the deleterious side reactions and allows the direct connection of guanidinium into stable phenyl rings. © 2011 American Chemical Society.

Cozzolino A.F.,McMaster University | Whitfield P.S.,NRC Institute for Chemical Process and Environmental Technology | Vargas-Baca I.,McMaster University
Journal of the American Chemical Society | Year: 2010

The remarkable effect that secondary bonding interactions can have on the macroscopic properties of a material is illustrated by two polymorphs of the title compound. The phase which is most stable under ambient pressure and temperature consists of puckered supramolecular ribbon polymers assembled by Te - N secondary bonding interactions and displays a characteristic red-orange color. A second yellow phase consists of ribbons with alternating short and long intermolecular Te - N secondary bonding distances and is metastable; at 127 °C the material undergoes an exothermic irreversible transition to the red polymorph. A third phase consists of pyridine-solvated supramolecular dimers; it is also yellow and transforms into the red phase after the crystals effloresce. Computational DFT studies indicate that the observed changes in optical properties are related to intermolecular mixing of π orbitals enabled by the supramolecular interactions and the symmetry of the supramolecular synthon. © 2010 American Chemical Society.

Liu F.,NRC Institute for Chemical Process and Environmental Technology | Smallwood G.J.,NRC Institute for Chemical Process and Environmental Technology
Applied Physics B: Lasers and Optics | Year: 2011

This study concerns the effect of soot-particle aggregation on the soot temperature derived from the signal ratio in two-color laser-induced incandescence measurements. The emissivity of aggregated fractal soot particles was calculated using both the commonly used Rayleigh-Debye-Gans fractal-aggregate theory and the generalized Mie-solution method in conjunction with numerically generated fractal aggregates of specified fractal parameters typical of flame-generated soot. The effect of aggregation on soot temperature was first evaluated for monodisperse aggregates of different sizes and for a lognormally distributed aggregate ensemble at given signal ratios between the two wavelengths. Numerical calculations were also conducted to account for the effect of aggregation on both laser heating and thermal emission at the two wavelengths for determining the effective soot temperature of polydisperse soot aggregates. The results show that the effect of aggregation on laser energy absorption is important at low fluences. The effect of aggregation on soot emissivity is relatively unimportant in LII applications to typical laminar diffusion flames at atmospheric pressure, but it can become more important in flames at high pressures due to larger primary particles and wider aggregate distributions associated with enhanced soot loading. © 2011 Her Majesty the Queen in Right of Canada.

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